In advance or high-performance optical systems, a shutter arm is often provided to stop light (or filter light) relative to a sensor (e.g., CCD, CMOS). One example is a typical twelve-color filter wheel that is rotated about an axis to place one or more filters in a light path relative to one or more sensors. However, the position of the shutter blade must be known and controlled to effectively control an amount of light received by a particular sensor. This requires a number of complex systems that may include position sensors, electronics controllers, processors, feedback loops, brushless DC motors, stepper motors, gearheads, gear trains, etc. Both brushless DC motors and stepper motors require complex drive electronics to commutate or step the motor to achieve the required motion of the shutter arm to control light emitted to the sensor. These components and control electronics are typically very expensive, and in space applications, they must be “space qualified” prior to use, which efforts are costly, cumbersome and time consuming.
Moreover, brushless DC motors and stepper motors are known as “contact” motors, which generate an appreciable amount of debris within systems when operated, which can be problematic to high-performance optical system and sensors.